This program project consists of a set of studies designed by individual or collaborating investigators with a common interest in developmental phenomena but trained in the disciplines of psychology, sociology, medicine and genetics. The studies capitalize upon the unusual breadth and perspective of a data base including physical, physiological, sociological, educational, cognitive and personality measures over the period from birth to 40 to 50 years in three longitudinal samples totaling over 300 men and women. There are also data of similar breadth over considerable periods of the life-span on the parents and offspring of the subjects. The objectives of the various component projects include analyses of: consistency and change in patterns of physical and mental health, cognitive (in the Piagetian sense) and moral (in Kohlberg's sense) level, and personality characteristics; early antecedents and adult correlates of participation in social networks, intellectual function, and physical health; interrelationships among cognitive, linguistic, moral, political-social, and personality characteristics; and kinship patterns in physical, cognitive, and moral development.